Typical Specification for performance of fittings for use with gasketed mechanical couplings used in piping applications For each house getting compared, the highest bar is AISI 304H stainless steel and the bottom bar is AISI 321H stainless steel. Disclaimer: Recommendations are for steering only, and the suitability of the material https://madanijayateknik.com/service/detail/round-bar-plate-sheet-pipe-tube-stainless-steel-321-uns-s32100-din-x6crniti18-10-aisi-321-dan-321h-uns-s32109-din-x8crniti18-10-aisi-321h